Lock for fire-alarm boxes.



4 F. w. COLE. LOCK FOR FIRE ALARM BOXES.

APPLICATION FILED APR. 18, $914.

Patented May16,1916,

wmmzayam jfiUiZZO/"X 22 72 3 5 uflc THE COLUMBIAYPLANOGRAPH c0..WASHINGTON. D. c.

FREDERICK W. COLE, OF NEVVT'ON, MASSACHUSETTS, ASSIGNOR TO GAMEWELL FIREALARM TELEGRAPH COMPANY, OF NEWTON UPPER FALLS, MASSACHUSETTS, A v

CORPORATION OF NEW YORK.

LOCK FOR FIRE-ALARM BOXES.

Specification of Letters Patent.

Patented May 16, 1916.

Application filed April 18, 1914.. Serial No. 832,943.

To all whom it may concern Be it known that I, FREDERICK W. COLE, acitizen of the United States, residing at Newton, in the county ofMiddlesex and State of Massachusetts, have invented an Improvement inLooks for Fire-Alarm Boxes, of which the following is a specification.

The doors of fire-alarm boxes are sometimes locked by means of more orless complicated locking-mechanisms adapted to be operated by a keywhich is removable from the lock; and sometimes by a bolt havingconnected With it a rotatable handle by which it is operated, as forinstance, in those types of fire-alarm boxes commonly known as keylessboxes; and sometimes by a lock having a key arranged in connection withit, which key is inclosed by a guard having a frangible front plate.Inthe latter case the key is sometimes inserted and left in the lock andsometimes is removed and adapted to be inserted. Many objections areurged against these various types of lockingmeans, some of which arereal and some imaginary, but the least objections are urged against thelatter type, wherein the key is inserted and left in the lock andinclosed by a guard.

This invention relates to the latter type -of locks for fire-alarm boXdoors, and has for its object the provision of a simple, cheap yetefficient form of device which may be easily and quickly applied to adoor and is not liable to get out of order, and furthermore, may bereadily applied to old types or forms of fire-alarm box doors, firstabove referred to, many of which are in use at the present time. p

The invention consists in arranging a sliding latch-bolt on the insideof the door, in a suitable bolt-casing, and in permanent operativeengagement with a key by which it'may be operated, and in employing acommon form of key-blank having a bit which may be projected through theusual key-hole, and then turned to bring its bit out of alinement withthe key-hole and into operative engagement with the latch-bolt, andproviding means to thereafter hold the bit of the key in approximatelysuch position so as to prevent it from being moved again into alinementwith the key-hole, thus to prevent subsequent withdrawal cfthe key. The

means for preventing the bit of the key from being moved into alinementwith the key-hole involves its association with the latch-bolt mechanismin some manner which necessitates the key being projected into thekey-hole and' turned before the latch-bolt mechanism is secured to theinside of the door, but any equivalent means falls within the scope ofmy invention which may be brought lnto position after the key has beenintroduced and turned to prevent the bit of the key from being againbrought into alinement with the key-hole.

The outer end or hand-engaging portion 3 of the key is inclosed in akey-guard arranged on the outside, of the door, which key-guard has afrangible front, such as a glass plate, which is designed to be brokento obtain access to the ke Figure l is a front elevation of a firealarmboX with key-guard and key embodying this invention. Fig. 2 is anenlarged rear side elevation of a portion of the door and the lock andkey in permanent engagement with the lock. Fig. '3- is a front elevationof the lock and key. Fig. 4 is a plan view of the lock and key. Fig. 5is an end elevation of the lock and key. Figs. 6 and 7 are modifiedforms of my invention. 7

The latch-bolt mechanism here shown comprises a latch-bolt 10, which issup back-plate and cross-pieces are or may be held assembledwith thelatch-bolt arranged in the-recesses of the cross-pieces, by-screws 21.,"or equivalent means which extend through holes in the back-plate andcrosspieces and into or through holes in the door 12, .so that thebolt-casing is thussecured to the inside of the door by the meansemployed for holding its component parts assembled. A spring 18 isconnected at one end to a pin or projection 19 on the "latch bolt 10,and at the other end to the backplate 15, which spring acts to throw thelatch-bolt in an outward direction or into locking position. Thisoutward movement of the latch-bolt is limited by a lug 20 arranged onthe back-plate and projecting forward into the path of movement of saidpin. Movement of the latch-bolt in the opposite direction is limited bysaid pin engaging the cross-piece 17. Said latch-bolt has arranged alongits under side one or more notches 22, three being here shown, and saidlatch-bolt and its casing are so arranged on the inside of the door thatone of said notches occupies a position just above the top of the usualkey-hole 23, in

the door. Three notches are here provided to accommodate differentfire-alarm box doors now in common use, which have their key-holesarranged at different distances from the edge.

25 represents a key, of simple form, having a single flat bit 26, andhaving the end-portion 27 of its shank extended beyond the bit. Suchakey may be an ordinary keyblank from which keys are usually made.

This key will be projected through the usual key-hole 23, in usualmanner, and its end-portion 27 will'enter one of the holes 28, in theback-plate 15; then said key will be turned a half revolution to bringits bit up into vertical position and above the keyhole for engagementwith one of the notches in the latch-bolt; and then the component partsof the bolt-casing with latch-bolt, are arranged on the inside of thedoor'with the latch-bolt engagement with the bit of the key and theparts thus assembled are secured inplace the screws 21, When the key isturned to the right, in the usual manner, the bolt will be moved toWithdraw it from locking-position, and subsequently will be caused toreturn to locking-position by means of the spring 18, when pressure uponthe key is relieved.

As the movement of the bolt is limited in both directions the key willbe permitted to turn only through a short arc in either direction, andwhile such movement of the key is 'suiiicient to move the latch-bolt itis notsuiiici'ent to disengage the latch-bolt, to admit otitsbeing againbrought into alinement with the key-hole, hence engagement of the keywith the latch-bolt becomes permanent, and subseq'uent withdrawal of thekey is prevented.

In lieu of holding the key with its bit out of alinement with thekey-hole by this particular means othenmeans may be employed, foraccomplishing the same result; and reiterringto Fig. 6 the latch-bolthas a longnotch with a shoulder at one end for engagementwith the bit ofthe key, and a pin 35 whichmay be on the back-plate 15, oron the insideof the d0or,'is arranged on that side of the bit of the key opposite theshoulder of the notch in the latch-bolt, thereby to limit the movementof the bit of the key through a short are and prevent it from beingbrought into alinement with the key-hole. Or, the modified form shown inFig. 7 may be employed wherein two pins 36, 37, arranged at oppositesides of the bit of the key are provided, which pins may be arranged onthe inside of the door, or on the back-plate of the latch-boltmechanism. In all these instances it will be observed that the key isfirst introduced and its bit brought into approximately verticalposition above the key-hole, and out of alinement therewith, and thenthe latch-bolt mechanism is placed in position on the inside of the doorand when secured thereto the key is held against being again turned tobring its bit into alinement with the keyhole, which it will beunderstood is the important feature of this invention.

80 represents a usual form of key-guard which may be applied to theoutside of the box-door, over the key-hole, to form a chamber to receivethe outer or hand-engaging portion of the key 25, said key-guard havinga frangible front-plate designed to be broken to obtain access to thekey.

My invention is to be especially contrasted with a key that is insertedin the 'lock and trapped, and is subsequently withdrawn when released.

I claim 2-- 1. A'fire-alarm box door having a keyhole, and a key-guardarranged on the outside of the door over said key-hole, latchboltmechanism comprising a sliding latchbolt and bolt-casing arranged on theinside of said door with a spring for moving said latch-bolt intolocking-position, and a key permanently arranged in the key-hole withits bit out of alinement therewith, said key being cooperativelyassembled with the component parts of the latch-bolt mechanism a'ndheldin permanent operative engagement with the bolt, in all positions saidbolt may occupy.

2. Afire-alarm box door having a keyhole, a key-guard arranged ontheoutside of the box door over said key-hole, a sliding latch-bolthaving a pluralityof notches, and a bolt-casing having a correspondingnumber of holes arranged on the inside of the door with a spring formoving said'bolt into locking position, meansfor limiting the slidingmovement of said boltin both directions, and a key permanentlyarrangedin the'keyhole with itsbit out of alinement therewith and inengagement with one of thenotch'es in the latch-bolt, and itsend-portion inengagement with one of the holes in the boltcasing, theslidingm'ovement ofthe latchbolt being limited to permit movement of thekey through a short are only,'whereby it is retained in permanentengagement there With, in all positions said bolt may occupy.

3. The combination with a fire-alarm door having a fragile guard memberupon its outer face, and a keyhole located Within the guard, of a lockincluding a movable looking element, and a key having its head portiondisposed Within the guard, and its bit in operative engagement With thelocking element, and means for preventing the disengagement of the keyfrom the locking element except upon disassemblage of the lock.

4. A lock including a casing secured to a member to be locked, saidmember being provided With a keyhole leading into the casing, a lockingelement movable in the casing, a key having its bit engaging With thelocking element, said bit being disengageable from the locking elementafter being turned through an arc of definite length, and means forpermanently preventing the movement of the bit through an arc of thelength required to disengage the bit from the lockingelement, wherebythe key may be Copies of this patent may be obtained for disassemblageof the lock.

Withdrawn from the casing, only upon the 5. A look including a casingsecuredto a member to be locked, said member being" pro- 7 vided with akeyhole leading into the casing, a locking element movable in thecasing, a key having its bit engaging with the locking element, said bitbeing disengageable from the locking element after being turned throughan arcof definite length, stop means FREDERICK W. COLE.

Witnesses B. J. NOYES, H. B. DAVIS.

five cents each, by addressing the Commissioner of Patents, Washington,D. O.

